Pasteurizers for the pasteurization of liquid contents, for example of containers filled with liquid contents, such as bottles, are known. Usually, a pasteurizer has a transport element formed from a conveyor belt. The belt moves containers in a transport direction through a plurality of zones of the pasteurizer. These zones follow one another and are separated from each other.
Within the zones, the containers are subjected to a warmed or heated liquid treatment medium, such as water. A first group of zones, which follows a container intake in the transport direction, is used for preheating. In order to increase the rate at which containers heat, the temperature of the treatment medium rises in steps from one zone to the next. Actual pasteurizing occurs within a group of zones that follows the preheating zones in the transport direction. In these pasteurizing zones, containers are subjected to a liquid treatment medium that has been heated to a pasteurizing temperature. The next and last zones in the transport direction are cooling zones in which the temperature of the treatment medium decreases step by step.
The treatment temperatures in the individual zones, and, in particular, in the zones that serve as pasteurizing zones, are adjusted in such a way that, by taking account the transport speed of the transport element, including in particular the dwell or treatment duration of the containers, each container is pasteurized in the proper manner. The curve of the treatment temperatures is adjusted in such a way that not only is an adequate pasteurization of the containers guaranteed, but the process itself adjusted in such a way that over-pasteurization is avoided, thus avoiding impairment of the taste quality of the contents.
Known pasteurizers are designed such that, during their operation, the transport speed of internal transport elements is constant or essentially constant. As a result, the treatment and dwell times of the containers in the pasteurizer, and the time containers spend in other zones, is also constant.
A pasteurizer is usually part of a system that carries out other container processing functions, such as filling, closing, equipping, or labeling containers.
Faults or any necessary reduction in performance or throughput within the parts of the overall system located upstream of the pasteurizer, for example inside the filling machine, often lead to a product deficiency, i.e. a deficiency of containers in a sector of the pasteurizer.
Conversely, faults or any necessary reduction in performance within the parts of the overall system located downstream of the pasteurizer, for example in a labeling machine or in a packing system, frequently lead to a product jam that extends outwards from the point of the fault. These jams can extend into the pasteurizer.
In the latter case, when a jam backs up into the pasteurizer, it can be necessary to switch off the transport element. This creates a risk of over-pasteurizing, which can impair product quality.
Even if a deficiency or product jam can be identified early, for example by a superordinate control device that controls the entire system, the conventional solution is to stop further inlet of containers into the pasteurizer or to allow the pasteurizer to run empty to rectify the production fault. As a result, no further containers are moved through the pasteurizer or its zones, and the drive of the pasteurizer is switched off. Such machine standstills cause, among other things, high energy and water consumption.
Known pasteurizers address these deficiencies by switching the transport element inside the pasteurizer on and off, and/or by controlling the quantity admitted into the zones in each case to accord with the treatment medium or liquid. These adjustments to production interruptions and/or production disturbances can be put into effect by the system control arrangement or by jam switches, which are provided on transporters of the system as a whole and/or downstream of the pasteurizer.